On Fri 15 Oct 07:45 PDT 2021, Lukasz Luba wrote:
> diff --git a/arch/arm64/include/asm/topology.h b/arch/arm64/include/asm/topology.h
[..]
> +/**
> + * topology_thermal_pressure_update() - Update thermal pressure for CPUs
> + * @cpus : The related CPUs for which capacity has been reduced
> + * @capped_freq : The maximum allowed frequency that CPUs can run at
I know this matches what I see in e.g. the Qualcomm cpufreq hw driver,
but in what cases will @capped_freq differ from
cpufreq_get_hw_max_freq(cpumask_first(cpus))?
Regards,
Bjorn
> + *
> + * Update the value of thermal pressure for all @cpus in the mask. The
> + * cpumask should include all (online+offline) affected CPUs, to avoid
> + * operating on stale data when hot-plug is used for some CPUs. The
> + * @capped_freq must be less or equal to the max possible frequency and
> + * reflects the currently allowed max CPUs frequency due to thermal capping.
> + * The @capped_freq must be provided in kHz.
> + */
> +void topology_thermal_pressure_update(const struct cpumask *cpus,
> + unsigned long capped_freq)
> +{
> + unsigned long max_capacity, capacity;
> + int cpu;
> +
> + if (!cpus)
> + return;
> +
> + cpu = cpumask_first(cpus);
> + max_capacity = arch_scale_cpu_capacity(cpu);
> +
> + /* Convert to MHz scale which is used in 'freq_factor' */
> + capped_freq /= 1000;
> +
> + capacity = mult_frac(capped_freq, max_capacity,
> + per_cpu(freq_factor, cpu));
> +
> + arch_set_thermal_pressure(cpus, max_capacity - capacity);
> +}
> +EXPORT_SYMBOL_GPL(topology_thermal_pressure_update);
> +
> static ssize_t cpu_capacity_show(struct device *dev,
> struct device_attribute *attr,
> char *buf)
> @@ -220,7 +255,6 @@ static void update_topology_flags_workfn(struct work_struct *work)
> update_topology = 0;
> }
>
> -static DEFINE_PER_CPU(u32, freq_factor) = 1;
> static u32 *raw_capacity;
>
> static int free_raw_capacity(void)
